Choice A is correct. The slope, , of a line in the xy-plane can be found using two points on the line, and , and the slope formula . Based on the given table, the line representing the relationship between and in the xy-plane passes through the points , , and , where is a constant. Substituting two of these points, and , for and , respectively, in the slope formula yields , which is equivalent to , or . Therefore, the slope of the line that represents this relationship in the xy-plane is .
Choice B is incorrect and may result from conceptual or calculation errors.
Choice C is incorrect and may result from conceptual or calculation errors.
Choice D is incorrect and may result from conceptual or calculation errors.